first off - space is BIG! unbelievably huge. and we haven't even finished exploring our own solar system, let alone all there to see out there in the big black empty universe. so don't get discouraged, or start believing we're all alone in the universe. And secondly, if we ever DID find evidence of life on alien planets, i'm pretty damn sure our government would cover it up. why? dude - we put people on secret no fly lists and keep files on every political action group just on the slight chance that they might have walked near someone who once knew a guy that dated a woman who emailed a website that COULD have been linked to a middle east terrorist group 10 years ago. secrets are just what we do. anything different shows up - ANYTHING at all, and the Fed will slap a top secret sticker on it and try to bury it for a decade just out of force of habit.

The problem is that we're looking for aliens that are just like us.Who says creatures on another planet are using radio? Who says they care about sending or receiving messages from us? There's been life on earth for 3.5 billion years and we're the first beings that give a sh*t about this sort of thing. Who says we'll even have the ability to understand each other in the slightest way? Modern humans have been around for 50,000 years and we can still barely communicate with our dogs, much less an alien species.

Rev. Skarekroe:The problem is that we're looking for aliens that are just like us.Who says creatures on another planet are using radio? Who says they care about sending or receiving messages from us? There's been life on earth for 3.5 billion years and we're the first beings that give a sh*t about this sort of thing. Who says we'll even have the ability to understand each other in the slightest way? Modern humans have been around for 50,000 years and we can still barely communicate with our dogs, much less an alien species.

Given the size of the Universe, the likelihood of the existence of extraterrestrial intelligence is pretty certain, however given the size of the Universe, the likelihood that we will find any (or they find us) is almost no chance. That doesn't mean we should stop looking, just that the odds are fairly depressing.

Everything we know about what life needs to exist suggests that the presence of life is probably a relatively recent phenomenon in the Universe. The only element robust enough to foster life is carbon which can only come from the cores of stars. Stars need to explode, die off, and eject their heavy matter to make planets and then life.

The early Universe was too hot and the early Stellar Era had no heavy elements. If life does exist out there, it's probably very young life that has only arrived very recently, like ours. If life is an overwhelming statistical inevitability, we might actually be the first of our kind - the earliest life-form to be consciously aware of its own existence and develop a means of escaping its home planet. As the Universe ages and more stars recycle heavy elements, the propensity for life existing elsewhere increases. That won't happen for hundreds of millions of years, however. We might be very lonely trailblazers. This is all highly speculative.

That other life hasn't contacted us is no indication that it does not exist. Distances in space are impossibly vast and it's a bit presumptuous to assume that other life is even trying to find us in the first place (or even wants to).

Furthermore, there's the Fermi paradox: That intelligent life in the Universe has such a short interstellar window that it goes extinct before it finds anyone else. Any advanced interstellar civilization that peaks and declines - possibly in a drastic way - in the order of thousands of years would appear as a mere blip-flash event to the cosmos at large; a flare-up of radiometry and extra-solar traffic rendered too short, too small, and too insignificant by the vastness of space to be detectable by anyone. A space-faring species would need to be around for tens of millions of years before anything else might detect it. The one thing the Fermi paradox might be suggesting isn't that there is no life out there but rather that traveling and/or communicating through space is very, very hard.

Ishkur:Given the size of the Universe, the likelihood of the existence of extraterrestrial intelligence is pretty certain, however given the size of the Universe, the likelihood that we will find any (or they find us) is almost no chance. That doesn't mean we should stop looking, just that the odds are fairly depressing.

Everything we know about what life needs to exist suggests that the presence of life is probably a relatively recent phenomenon in the Universe. The only element robust enough to foster life is carbon which can only come from the cores of stars. Stars need to explode, die off, and eject their heavy matter to make planets and then life.

The early Universe was too hot and the early Stellar Era had no heavy elements. If life does exist out there, it's probably very young life that has only arrived very recently, like ours. If life is an overwhelming statistical inevitability, we might actually be the first of our kind - the earliest life-form to be consciously aware of its own existence and develop a means of escaping its home planet. As the Universe ages and more stars recycle heavy elements, the propensity for life existing elsewhere increases. That won't happen for hundreds of millions of years, however. We might be very lonely trailblazers. This is all highly speculative.

That other life hasn't contacted us is no indication that it does not exist. Distances in space are impossibly vast and it's a bit presumptuous to assume that other life is even trying to find us in the first place (or even wants to).

Furthermore, there's the Fermi paradox: That intelligent life in the Universe has such a short interstellar window that it goes extinct before it finds anyone else. Any advanced interstellar civilization that peaks and declines - possibly in a drastic way - in the order of thousands of years would appear as a mere blip-flash event to the cosmos at large; a flare-up of radiometry and extra-solar traffic rendered too short, too small, and too insignifican ...

It's just as plausible Earf is the beginning of life and it is we who will spread it throughout the galaxy and beyond.

cman:How do we know that aliens use the same kind of radio technology that we do?

Electromagnetic radiation is electromagnetic radiation. We've got a pretty good handle on it, we know the entire spectrum, and we know where we should look, and where we'd be wasting our time looking for various reasons.

86 stars were selected for this directed search, and over a period of three months in 2011 (February to April), the Green Bank antennae detected 52 candidate narrow-band radio signals (less than 5 Hz) between 1-2 GHz.

As for the story, it is a small swath of space, and these are signals that would have to travel at the speed of light, so if they are 1,000 light years away, it just means that no little green men were transmitting from those planets 1,000 years ago.

Ishkur:That other life hasn't contacted us is no indication that it does not exist.

Are you sure it hasn't? Consider, we're currently just listening for signals. If we found one, wouldn't the next logical step be to transmit a loud signal at one we detected, and then keep listening and wait for a response? Say, transmit something like:So, maybe it's silent because we haven't replied?

A 100,000 Watt radio source, radiating omnidirectionally, produces 0.000000796 Watts at 100 kilometers. At 100 light-years, the signal strength has degraded to 0.000000000000000000000000014 W, much less than the interstellar background noise.

So unless aliens have a bigass transmitter aimed directly at Earth, we aren't going to find them with radio.

It has nothing to do with how big the universe is and has everything to do with "we don't know what we're looking for."

As someone on Through the Wormhole explained, we shouldn't be looking for words, but instead for various patterns that exist in all communication in all forms of life.

The other issue, as others have pointed out, is that we may not even be capable of detecting the forms of communication being used. An analogy would be looking for a letter when aliens are sending email.

Ishkur:Furthermore, there's the Fermi paradox: That intelligent life in the Universe has such a short interstellar window that it goes extinct before it finds anyone else. Any advanced interstellar civilization that peaks and declines - possibly in a drastic way - in the order of thousands of years would appear as a mere blip-flash event to the cosmos at large; a flare-up of radiometry and extra-solar traffic rendered too short, too small, and too insignificant by the vastness of space to be detectable by anyone. A space-faring species would need to be around for tens of millions of years before anything else might detect it. The one thing the Fermi paradox might be suggesting isn't that there is no life out there but rather that traveling and/or communicating through space is very, very hard.

Heck, from what I understand most of our radio communications nowadays don't propagate out to space as we have switched from high voltage inefficient designs to low voltage efficient designs. Is as if we used flood lamps to light our way everyone for about 100 years, then we quickly switched the small little led lights and wonder why people on other planets are seeing them.

I've always though the "fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space" factor of the Drake equation to be over-estimated at 10-20%.

Heck, from what I understand most of our radio communications nowadays don't propagate out to space as we have switched from high voltage inefficient designs to low voltage efficient designs. Is as if we used flood lamps to light our way everyone for about 100 years, then we quickly switched the small little led lights and wonder why people on other planets are seeing them.

From what I understand, a radio telescope could detect very faint radio broadcasts from 100s of light years away. But given our increasing demand for wireless data, any civilization that used radio technology would be likely to use low powered short range transmissions to maximize available bandwidth.

cman:How do we know that aliens use the same kind of radio technology that we do?

We don't. For all we know, that subspace communication in Star Trek could be real.

Electromagnetic radiation is a vital component to the physical universe; it's unlikely any technic civilization could develop without a thorough study of it, including radio waves. The aliens might not use radio technology, but they'd almost certainly be familiar with its basic principles.

Cthulhu_is_my_homeboy:A 100,000 Watt radio source, radiating omnidirectionally, produces 0.000000796 Watts at 100 kilometers. At 100 light-years, the signal strength has degraded to 0.000000000000000000000000014 W, much less than the interstellar background noise.

So unless aliens have a bigass transmitter aimed directly at Earth, we aren't going to find them with radio.

You could detect a 100,000 watt omnidirectional (something that isn't practical, but let's go with it) radio signal with the Arecibo telescope out to about 2,470 AU.

If the Alienses used even a moderately more powerful transmitter, say, 10 megawatts (something we can do now ourselves), you could detect that at about 1/10th the distance to Proxima Centauri.

But even here on Earth, no one uses omnidirectional antennas. Even a modest dish antenna of 30 feet in diameter, transmitting 10 megawatts, could be detected by Arecibo at a distance of around 350 light years.

Right now, an alien Arecibo equivalent could detect our current ballistic missile early warning radars out to perhaps 8 light years, and the old DEW Line radars out to something like 12 light years.

The search for intelligent life in the universe is very much akin to a religious quest. With SETI we have gone in assuming that radio waves are a milepost on the road to civilization. We set out looking for OURSELVES!No wonder SETI has not found anything and likely NEVER will. It is the wrong tool for the job. In other words it has been a waste of resources that could have been better spent.

Intelligence probably exists elsewhere in the universe, however interstellar distances effectively isolate any intelligence from ever contacting another like itself. For all intents and purposes we ARE alone in the universe.

Delawheredad:Intelligence probably exists elsewhere in the universe, however interstellar distances effectively isolate any intelligence from ever contacting another like itself. For all intents and purposes we ARE alone in the universe.

Kazan:Rev. Skarekroe: The problem is that we're looking for aliens that are just like us.Who says creatures on another planet are using radio? Who says they care about sending or receiving messages from us? There's been life on earth for 3.5 billion years and we're the first beings that give a sh*t about this sort of thing. Who says we'll even have the ability to understand each other in the slightest way? Modern humans have been around for 50,000 years and we can still barely communicate with our dogs, much less an alien species.

math is the universal language

It's entirely possible our understanding of mathematics is so crude, relatively speaking, that even broadcasting a mathematical message wouldn't be worth a more advanced species' time.

Simple mathematics. The odds of intelligent life forming are unknown. For intelligence to evolve on our planet for example several major extinctions had to happen first. The dinosaurs ruled the planet for millions of years and never developed intelligence. Therefore on our OWN planet intelligent life is not the norm of the planet's evolution. We have no way of guessing how intelligence evolves on other planets or even if intelligence like ours is a natural end result of evolution. A LOT of things had to happen for us to inherit this planet. For all we know we ARE cosmic accidents.

The likely hood of that accident happening billions of times as SETI proponents wish to believe is only a wishful conjecture. Intelligent life in the universe is more than likely scattered on distant outposts throughout the galaxies. The odds of any two of those intelligences coming in contact with each other are infinitesimally remote.

The best situation for humanity is to live like we are the only intelligence in the universe. No aliens are coming to share their wisdom with us, the cavalry is not coming charging over the hills, so we have to live as though we are the only spark of intelligence in the galaxy, We are it, We don't get a second chance. we need to preserve our earth, terraform other planets and spread throughout the solar system and eventually the nearby stars. Like the humans at the end of The Martian Chronicles in order to meet aliens we have to become them.

Delawheredad:Simple mathematics. The odds of intelligent life forming are unknown. For intelligence to evolve on our planet for example several major extinctions had to happen first. The dinosaurs ruled the planet for millions of years and never developed intelligence. Therefore on our OWN planet intelligent life is not the norm of the planet's evolution.

There is no indication that our planet is in any way better or worse towards germinating advanced life than the expected universal norm. We have no standard of comparison from which to make an assertion as to whether life on other worlds must go through the same rigorous processes as ours does.

Our planet may be optimal. It may be sub-optimal. It may be average. The history of life on this planet may be typical. It may be unusual. It may be inevitable. Intelligence on other worlds may take only a few million years to evolve, or a few billion years longer than it has here.

dittybopper:Right now, an alien Arecibo equivalent could detect our current ballistic missile early warning radars out to perhaps 8 light years, and the old DEW Line radars out to something like 12 light years.

Yeah, but space is huge, and directional antennae have to be pointed towards each other or there'll be no signal at all. The omnidirectional radiator is sort of the "best case scenario" because it doesnt have to line up. Although I doubt I have to explain that to Fark's resident radio expert, heh.

I figure the major problem is any alien civilization is going to do more or less what we do: aim their radio transmitters mainly toward their own planet. It's pretty long odds that we'll ever have a dish pointed at the right part of the sky just in time to catch backscatter from an alien early warning radar. And then there's hoping the aliens are close enough for us to be able to detect them at all. We'd have a bear of a time detecting alien radars on the other side of the Milky Way.

Contrabulous Flabtraption:It's entirely possible our understanding of mathematics is so crude, relatively speaking, that even broadcasting a mathematical message wouldn't be worth a more advanced species' time.

a species more advanced than us would likely try to decode the message for the same reason we would: curiosity.

Contrabulous Flabtraption:Kazan: Rev. Skarekroe: The problem is that we're looking for aliens that are just like us.Who says creatures on another planet are using radio? Who says they care about sending or receiving messages from us? There's been life on earth for 3.5 billion years and we're the first beings that give a sh*t about this sort of thing. Who says we'll even have the ability to understand each other in the slightest way? Modern humans have been around for 50,000 years and we can still barely communicate with our dogs, much less an alien species.

math is the universal language

It's entirely possible our understanding of mathematics is so crude, relatively speaking, that even broadcasting a mathematical message wouldn't be worth a more advanced species' time.

Alien:

"Ohhhh, 'math'! You guys are using math. Yeah, we tried that a long time ago. Turns out it doesn't really go anywhere. Kind of a dead end."

Cthulhu_is_my_homeboy:dittybopper: Right now, an alien Arecibo equivalent could detect our current ballistic missile early warning radars out to perhaps 8 light years, and the old DEW Line radars out to something like 12 light years.

Yeah, but space is huge, and directional antennae have to be pointed towards each other or there'll be no signal at all. The omnidirectional radiator is sort of the "best case scenario" because it doesnt have to line up. Although I doubt I have to explain that to Fark's resident radio expert, heh.

I figure the major problem is any alien civilization is going to do more or less what we do: aim their radio transmitters mainly toward their own planet. It's pretty long odds that we'll ever have a dish pointed at the right part of the sky just in time to catch backscatter from an alien early warning radar. And then there's hoping the aliens are close enough for us to be able to detect them at all. We'd have a bear of a time detecting alien radars on the other side of the Milky Way.

Actually, we have a whole mess of high powered transmitters aimed at the sky. In fact, almost all of them are, if you think about it: radars, TV transmitters, and things like point-to-point microwave links don't actually point at the ground, they point at the horizon, which means that most if not all of their signal is going to go out into space. True, they don't point straight up, but at microwave frequencies, that doesn't matter: The ionosphere isn't going to block them from going out into space.

This sort of thing has been known for years. Sagan and Shklovskii talked about how you could actually get a decent outline of the continents on Earth by mapping out the TV transmitters and radars, noting when they popped up over the horizon and when they dropped back down back in the 1960's.

Crunch61:I've always though the "fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space" factor of the Drake equation to be over-estimated at 10-20%.

It's a fluke that we ever got past huts and tepees.

Nah, without metals we could have floated along as hunters and gatherers and agrarian Neolithic peoples for eons and eons, but once bronze was developed modern technological civilization was pretty much inevitable.

Tanukis_Parachute:so does this mean i can uninstall the little seti project app from my windows 95 computers?

If you don't look, you don't find. Of what use is a Windows 95 computer, if not for doing long, slow busy work while you use your good computer to play video games and download pron faster than you could have believed possible five years ago? We've got way too much obsolete or aging technology to junk it all safely and profitably. Might as well use it for public goods.

The SETI researchers aren't surprised by not finding anything because they are perfectly aware of the difficulties and risks of the task they have assigned themselves. Ten years, twenty years, a century, a millennium ... nobody knows how long it might take, although most of the leaders don't expect short or even medium term results but the importance of the question is enough to drive the search. The SETI searchers are well aware that aliens might not broadcast radio signals--but they assume that since at least one species has been dumb enough to do it, other species are likely to be on the same low level of development. In fact, many of the galaxy's species may not have basic cable and may spend their time on the web telling each other that they don't even have a TV.

The universe may be full of hostile monsters who destroy every semi-intelligent species they meet in order to prevent rivals from developing superior organization and power, or it may be full of hipsters who can't be bothered to talk to radio-broadcasting civilizations because we're so primitive we haven't created a sub-universe yet.

But the search goes on and as new ideas for finding signs of life and intelligence occur to researchers, they will be implemented.

At the moment we can just barely detect giant planets in tight orbits around their stars by looking for wobbles and slight regular blips of light such as are produced when you throw a quarter up into the air between a distant observer and a bonfire. We don't know how much of what we consider life to be is universal or peculiar to our world's history.

But it's worth while to think about and search for answers to questions that may take centuries to answer.

After all, we are kept quite amused with questions that took thousands of years to think up, let alone answer. Many of the mathematical puzzles set by mathematicians over the last 400 years have been answered--sometimes with answers that run to book or encyclopedia size--and many remain, generating new puzzles.

I am one of those who do not mourn the loss of a mystery. As somebody observed, there are plenty more mysteries and always will be. Solve one problem, it creates a whole set of new problems of various orders of magnitude greater or smaller than the original problem. Mysteries are unlikely to run out while our species exists in some form or other.

BafflerMeal:"Ohhhh, 'math'! You guys are using math. Yeah, we tried that a long time ago. Turns out it doesn't really go anywhere. Kind of a dead end."

Yes, we like totally worked it out. At first we were like "What is this shiat? It don't make no sense, this is like when you see your Mum without her glasses and it don't look like your Mum no more and you're scared".

Yeah, for real, then we worked it out using maths, long division, timesing, carry the four remainder two, that sort of business.

Contrabulous Flabtraption:Kazan: Rev. Skarekroe: The problem is that we're looking for aliens that are just like us.Who says creatures on another planet are using radio? Who says they care about sending or receiving messages from us? There's been life on earth for 3.5 billion years and we're the first beings that give a sh*t about this sort of thing. Who says we'll even have the ability to understand each other in the slightest way? Modern humans have been around for 50,000 years and we can still barely communicate with our dogs, much less an alien species.

math is the universal language

It's entirely possible our understanding of mathematics is so crude, relatively speaking, that even broadcasting a mathematical message wouldn't be worth a more advanced species' time.

I believe the goal isn't to impress an advanced civilization with our math skills. IIRC we have sent out something pretty basic like the first few prime numbers on a repeating loop (one beep, then two, then three, five, seven, back to one) the goal is to make a "WE'RE HERE!" sort of announcement.

Along those lines, any species advanced enough to reach earth from a world light years away probably won't be interested in our tech, at most it will be for scientific reasons, the same way humans study chimps...or dust mites.

JRaynor:Along those lines, any species advanced enough to reach earth from a world light years away probably won't be interested in our tech, at most it will be for scientific reasons, the same way humans study chimps...or dust mites.

I would imagine if we were contacted by aliens it would be as you say, curiosity. They won't be interested in our tech, resources, or even slave labor. They could get all of those much easier and cheaply than crossing vast distances. They would want to know who/what we are and MAYBE sell us dumb natives trinkets.

hutchkc:JRaynor: Along those lines, any species advanced enough to reach earth from a world light years away probably won't be interested in our tech, at most it will be for scientific reasons, the same way humans study chimps...or dust mites.

I would imagine if we were contacted by aliens it would be as you say, curiosity. They won't be interested in our tech, resources, or even slave labor. They could get all of those much easier and cheaply than crossing vast distances. They would want to know who/what we are and MAYBE sell us dumb natives trinkets.